TWI505638B - Power system with hot-swap and the method thereof - Google Patents

Description

Hot swappable power system

The present invention relates to an electronic circuit, and more particularly to a power plugging (hot plugging) power system and method therefor.

Hot-swap technology is often used when inserting a hard disk drive, board, etc. in a running system, or removing the peripherals from a running system. The prior art typically employs a field effect transistor operating in a low dropout mode for hot plugging, as shown in Figure 1a.

FIG. 1a shows a schematic diagram of the circuit structure of an existing hot swappable power system 10. The hot swappable power system 10 shown in FIG. 1a includes a front stage 11 that supplies a supply voltage V _IN , the front stage 11 includes a front stage capacitor C _IN , and a hot plug stage 12 coupled to the front stage 11 for receiving power. The voltage V _IN and the output voltage V _O is provided based on the supply voltage V _IN ; the load stage 13 is coupled to the hot plug stage 12 to receive the output voltage V _O , and the load stage 13 includes an output capacitor C _O . Typically, the hot swap stage 12 and the load stage 13 are placed on a motherboard. In the embodiment shown in FIG. 1a, the hot plug stage 12 includes a metal oxide semiconductor field effect transistor M1 (MOSFET) and a controller. Wherein, when the motherboard plug before stage 11 (i.e., start), the controller controls the operation of low voltage differential mode MOSFET, gradually increases from zero to produce an output voltage V _O.

Figure 1b shows the voltage drop V _DS between the output voltage V _O , the MOSFET M1 汲 terminal (D) and the source terminal (S), the current I _S flowing through the MOSFET, and the hot-swappable power system 10 shown in Figure 1a. Schematic diagram of the power dissipation of MOSFET M1 P_ _MOS . Since the MOSFET M1 operates in the low dropout mode, the output voltage V _O gradually increases from zero to the supply voltage V _IN minus the saturation voltage drop of the MOSFET M1. However, since the supply voltage V _IN remains constant, the drain-source voltage drop V _{DS of the} MOSFET M1 gradually decreases from the supply voltage V _IN to its saturation voltage drop. In addition, during the startup of the motherboard in the previous stage, the load stage 53 operates in the current source mode to draw current, and the current flowing through the MOSFET M1 includes the load current and the current flowing through the output capacitor C _O . Therefore, a large amount of power consumption will be generated on the MOSFET M1. Although the power system startup process is very short compared to its entire operating process, the power dissipation on the MOSFET M1 increases the thermal design requirements of the system. Especially in high current applications, multiple MOSFETs and a large amount of motherboard space will be used for heat dissipation, wasting the thermal design of the system under normal operation.

Accordingly, it is an object of the present invention to solve the above-described technical problems of the prior art and to provide an improved hot swappable power system and method therefor.

According to an embodiment of the present invention, a hot-swappable power system is provided, comprising: a front stage providing a constant supply voltage at an output terminal thereof, wherein the front stage includes coupling between a front stage output terminal and a reference ground a pre-stage capacitor; a hot-swappable stage coupled to the output terminal of the pre-stage to receive a supply voltage and generating an output voltage based on the supply voltage, the hot-swap stage comprising: a buck converter having a main power device And a controller, the controller including a first input terminal, a second input terminal, and an output terminal, the first The input terminal receives a current sampling signal representing a flow through the main power device, the second input terminal receives a voltage feedback signal representative of the output voltage, and the controller generates a switch control signal at its output terminal based on the current sampling signal and the voltage feedback signal, The main power device is controlled to operate in a switch mode, the hot plug stage generates an output voltage based on the on and off of the main power device; and the load stage is coupled to the hot plug stage to receive the output voltage.

According to an embodiment of the present invention, a hot-swappable power system is further provided, comprising: a front stage providing a constant supply voltage at an output terminal thereof, the front stage including a front stage coupled to the front stage output terminal and the reference ground a capacitor; a hot plug stage coupled to the output terminal of the front stage to receive the power supply voltage, and generating an output voltage based on the power supply voltage, the hot plug stage comprising: a main power device having a first terminal and a second terminal And a control terminal, the first terminal is coupled to the output terminal of the front stage to receive the power supply voltage; the freewheeling device is coupled between the second terminal of the main power device and the reference ground; and the inductor has the first terminal And a second terminal, the first terminal of which is coupled to the second terminal of the main power device, the second terminal of which generates the output voltage; the controller has a first input terminal, a second input terminal, and an output terminal, An input terminal receives a current sampling signal representing a flow through the main power device, a second input terminal thereof receives a voltage feedback signal representative of an output voltage, and the controller is based on the current sampling signal and voltage Feeding a signal to generate a switch control signal at its output terminal for controlling the main power device to operate in a switch mode; the hot plug stage generates an output voltage based on the on/off of the main power device; load level, coupling Connect to the hot-swap stage to receive the output voltage.

According to an embodiment of the present invention, a hot plug power system is also proposed The system includes: a pre-stage, providing a supply voltage having a negative voltage level at an output terminal thereof, the pre-stage comprising a front-end capacitor coupled between the pre-stage output terminal and the reference ground; and the hot-swapping stage, comprising: The main power device has a first terminal, a second terminal and a control terminal, the first terminal of which is coupled to the output terminal of the front stage to receive the power supply voltage; and the freewheeling device is coupled to the second terminal of the main power device Between the reference grounds, the inductor has a first terminal and a second terminal, the first terminal of which is coupled to the second terminal of the main power device, and the controller has a first input terminal, a second input terminal, and an output terminal, The first input terminal receives a current sampling signal representing the flow through the main power device, the second input terminal receives a voltage feedback signal representative of the output voltage, and the controller generates a switch at its output terminal based on the current sampling signal and the voltage feedback signal a control signal for controlling operation of the main power device in a switch mode; wherein the hot plug stage is based on the on and off of the main power device at a second terminal of the inductor The output voltage is generated between the reference ground; load stage, coupled to the hot plug line to receive the output voltage level.

In accordance with an embodiment of the present invention, a method for hot plugging a power system is also provided, comprising: placing a hot plug stage and a load stage on a motherboard, wherein the hot plug stage includes a main power device a buck converter; plugging the main board into a power system; controlling the main power device to operate in a switching mode to generate an output voltage at an output terminal of the hot plug stage, wherein, during the plugging process, the main The duty cycle of the power device is gradually increased from 0% to 100%; the duty cycle of the main power device is maintained at 100% after the end of the plug-in process and during normal operation of the power system.

The above-described hot-swappable power system and method thereof according to various aspects of the present invention greatly reduce the power loss during the "plug-in" process, and optimize the thermal design of the system.

The embodiments of the present invention are described in detail below, and it should be noted that the embodiments described herein are by way of illustration only and are not intended to limit the invention. In the following description, numerous specific details are set forth in order to provide a However, it will be apparent to those skilled in the art that the invention In other instances, well-known circuits, materials, or methods have not been specifically described in order to avoid obscuring the invention.

References throughout the specification to "one embodiment", "an embodiment", "an" or "an" or "an" In at least one embodiment. The appearances of the phrase "in one embodiment", "in the embodiment" Furthermore, the particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and/or sub-combination. In addition, those skilled in the art should understand that the drawings are provided for the purpose of illustration, and the drawings are not necessarily drawn to scale. It will be understood that when an element is "coupled" or "connected" to another element, it can be directly coupled or coupled to the other element or the intermediate element. in contrast In the meantime, when an element is referred to as being "directly coupled" or "directly connected" to another element, there is no intermediate element. The same reference numbers indicate the same elements. The term "and/or" used herein includes any and all combinations of one or more of the associated listed items.

2 shows a circuit configuration diagram of a power system 100 in accordance with one embodiment of the present invention. In the embodiment shown in FIG. 2, the power system 100 includes a front stage 101 that provides a constant supply voltage V _IN at its output terminal, wherein the front stage 101 includes an output terminal coupled to the front stage 101 and a reference ground. foreline between the capacitor C _iN; hot plug stage 102, system 101 coupled to the output terminal of the previous stage to receive a supply voltage V _iN, based on the supply voltage V _iN and generates an output voltage V _O, the hot swap Stage 102 includes a buck converter having a main power device 21 and a controller 24, the controller 24 including a first input terminal, a second input terminal, and an output terminal, the first input terminal of which receives a representative flow through the main power device The current sampling signal I _{sense of} 21, the second input terminal thereof receives a voltage feedback signal V _FB representing the output voltage V _O , and the controller 24 generates a switch at its output terminal based on the current sampling signal I _sense and the voltage feedback signal V _FB A control signal for controlling the main power device 21 to operate in a switching mode, the hot plug stage 102 generating a desired output voltage V _O based on the on and off of the main power device 21. The power system further includes a load stage 103 coupled to the hot plug stage 102 to receive the output voltage V _O .

In one embodiment, the voltage level of the output voltage V _O is substantially equal to the voltage level of the supply voltage V _IN .

In the embodiment shown in FIG. 2, the buck converter further includes: a freewheeling device 22 having a first terminal and a second terminal, the first terminal of which is coupled to the main power device 21; the inductor 23, Having a first terminal and a second terminal, the first terminal of which is coupled to the first terminal of the freewheeling device 22; wherein, between the second terminal of the freewheeling device 22 and the second terminal of the inductor 23 The potential difference is the output voltage V _O .

In one embodiment, the primary power device 21 comprises a metal oxide semiconductor field effect transistor (MOSFET). However, in other embodiments, the main power device 21 may further include an insulated gate bipolar transistor (IGBT), a bipolar junction transistor (BJT), or the like.

In one embodiment, the freewheeling device 22 includes a diode. However, in other embodiments, the freewheeling device 22 may further comprise a controllable semiconductor device, such as a metal oxide semiconductor field effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), and a bipolar junction type. Transistor (BJT) and so on.

In one embodiment, the load stage 103 includes a telecommunications line card, a network switch/router, a central office line card, a server line card, a base station line card, and the like.

In one embodiment, the supply voltage V _IN has a voltage level of 48 volts or 12 volts.

FIG. 3 shows a circuit configuration diagram of a power system 200 in accordance with an embodiment of the present invention. The power system 200 shown in FIG. 3 shows a circuit configuration diagram of the controller 24. In the embodiment shown in FIG. 3, the controller 24 includes a current comparator 41 having a first input terminal, a second input terminal, and an output terminal, the first input terminal of which receives a current sample representative of the flow through the main power device 21. The signal I _sense , the second input terminal thereof receives the current reference signal I _ref , and the current comparator 41 generates a current comparison signal I _com at its output terminal based on the current sampling signal I _sense and the current reference signal I _ref to ensure flow The current of the main power device 21 does not exceed a preset value, that is, the current sampling signal I _{sense is} followed by the current reference signal I _ref ; the amplifier 42 has a first input terminal, a second input terminal and an output terminal, the first input thereof The terminal receives the voltage feedback signal V _FB , the second input terminal receives the voltage reference signal V _ref , and the amplifier 42 generates an amplified signal V _com at its output terminal based on the voltage feedback signal V _FB and the voltage reference signal V _ref to ensure the voltage with the feedback signal V _FB with a reference voltage signal V _ref: 43 and logical drive unit, having a first input terminal, a second input terminal and an output Terminal, a first input terminal coupled to the current-based output terminal of comparator 41 to receive the comparison signal current I _com, a second input coupled to the output terminal of the line terminal of the amplifier 42 to receive the amplified signal V _com, the logic The drive unit 43 generates a switch control signal at its output terminal based on the current comparison signal _Icom and the amplification signal _Vcom to control the main power device 21.

In one embodiment, the voltage feedback signal V _FB is delivered to a first input terminal of the amplifier 42 via a preamplifier (not shown).

In one embodiment, the voltage reference signal V _ref is variable. In one embodiment, when the voltage level of the output voltage V _O substantially reaches the voltage level of the supply voltage V _IN , the time derivative of the voltage reference signal V _ref is zero, that is,

In one embodiment, the output voltage V _O increases linearly at the beginning, but after a certain time point t1, the output voltage V _O begins to increase exponentially, as shown in FIG.

FIG. 5 shows a circuit configuration diagram of a power system 300 in accordance with an embodiment of the present invention. The power system 300 shown in FIG. 5 shows another circuit configuration diagram of the controller 24. In the embodiment shown in FIG. 5, the controller 24 includes a current comparator 41 having a first input terminal, a second input terminal, and an output terminal, the first input terminal of which receives a current sample representative of the flow through the main power device 21. The signal I _sense , the second input terminal thereof receives the current reference signal I _ref , and the current comparator 41 generates a current comparison signal I _com at its output terminal based on the current sampling signal I _sense and the current reference signal I _ref ; the voltage reference signal is generated 44, a voltage reference signal V _ref, the voltage reference signal V _ref increases linearly with a slope in the beginning, but after a certain point in time, with an exponential increase slope; amplifier 42, having a first input terminal, a second input a terminal and an output terminal, the first input terminal of which receives the voltage feedback signal V _FB , the second input terminal of which is coupled to the voltage reference signal generator 44 to receive the voltage reference signal V _ref , the amplifier 42 is based on the voltage feedback signal V _FB And a voltage reference signal V _ref to generate an amplified signal V _com at its output terminal; and a logic driving unit 43 having a first input terminal, The second input terminal and the output terminal are coupled to the output terminal of the current comparator 41 to receive the current comparison signal I _com , and the second input terminal is coupled to the output terminal of the amplifier 42 to receive the amplified signal V _com , the logic driving unit 43 generates a switching control signal at its output terminal based on the current comparison signal I _com and the amplification signal V _com to control the main power device 21 .

In the embodiment shown in FIG. 5, the voltage reference signal generator 44 includes an exponential signal generator 45 that produces an exponential signal _Vexp having an exponentially increasing slope, and a linear signal generator 46 that produces a linearity with a linear growth slope. a signal V _lin ; and a selector 47 having a first input terminal, a second input terminal and an output terminal, the first input terminal of which is coupled to the index signal generator 45 to receive the exponential signal V _exp , and the second input terminal thereof Coupling to the linear signal generator 46 to receive the linear signal V _lin , the selector 47 uses the signal with a lower voltage level as the voltage reference of its output terminal based on the index signal V _exp and the linear signal V _lin Signal V _ref .

In one embodiment, the index signal generator 45 includes: an output node 54; a first capacitor 53 coupled between the output node 54 and a reference ground; and a voltage source 51 and a resistor 52 coupled in series Between the output node 54 and the reference ground; wherein the index signal _Vexp is generated at the output node 54. In one embodiment, the voltage level of the voltage source 51 corresponds to the voltage level of the desired output voltage.

In one embodiment, the linear signal generator 46 includes a current source 61 that generates a current signal, and a second capacitor 62 coupled between the current source 61 and a reference ground, wherein the linear signal V _lin is A coupling node is generated at the current source 61 and the second capacitor 62.

When the load stage is plugged into the front stage, power system 300 begins to operate. On the one hand, the current source 61 begins to charge the second capacitor 62, and the voltage across the second capacitor 62 begins to increase linearly. On the other hand, the voltage source 51, the resistor 52 and the first capacitor 53 form a current loop, and the voltage source 51 charges the first capacitor 53, the voltage across the first capacitor 53 (i.e., the voltage of the exponential signal _Vexp ) and The voltage level of the voltage source 51 satisfies the following relationship:

Wherein C ₅₃ represents the capacitance value of the first capacitor 53, and R ₅₂ represents the resistance value of the resistor 52, Representing the time derivative of the exponential signal _Vexp , _V51 represents the voltage level of the voltage source 51. As can be seen from equation (1), the exponential signal V _exp has an exponential growth slope.

As shown in FIG. 4, at the beginning, the slope of the linear signal _Vlin is less than the slope of the exponential signal _Vexp , at which time the linear signal _{Vlin is} less than the exponential signal _Vexp . Accordingly, the selector 47 selects the linear signal V _lin as the voltage reference signal V _ref . However, as shown in FIG. 4, the index signal V _exp starts to be smaller than the linear signal V _lin from the time t1. Accordingly, the selector 47 selects the index signal V _exp as the voltage reference signal V _ref . Therefore, as the voltage reference signal V _ref increases, the duty ratio of the main power device 21 smoothly increases from 0% to 100%. When the output voltage V _O substantially reaches the voltage level of the supply voltage V _IN , the time derivative of the voltage reference signal V _ref is substantially zero, and the duty cycle of the main power device 21 is substantially 100%. Therefore, the current flowing through the inductor 23 is substantially zero to ensure that there is no oscillation in the buck converter after the start of the startup process.

FIG. 6 shows a circuit configuration diagram of a power system 400 in accordance with an embodiment of the present invention. The power system 400 shown in FIG. 6 shows still another circuit configuration diagram of the controller 24. In the embodiment shown in FIG. 6, the controller 24 includes an amplifier 42 having a first input terminal, a second input terminal, and an output terminal, the first input terminal receiving the voltage feedback signal V _FB and the second input terminal receiving a voltage reference signal V _ref , the amplifier 42 generates an amplification signal at its output terminal based on the voltage feedback signal V _FB and the voltage reference signal V _ref ; the current comparator 41 has a first input terminal, a second input terminal, and an output terminal, The first input terminal receives a current sampling signal I _sense representing the flow through the main power device 21, the second input terminal is coupled to the output terminal of the amplifier 42 to receive the amplified signal, and the current comparator 41 is based on the current sampling signal I. _{The sense} and the amplified signal generate a current comparison signal I _com at its output terminal; and the logic driving unit 43 is coupled to the output terminal of the current comparator 41 to receive the current comparison signal I _com , and based on the current comparison signal I _com A switch control signal is generated to control the main power device 21.

The power system of the above embodiments is configured as a closed loop control with voltage feedback and voltage reference signals during a "plugging" process, but those skilled in the art will appreciate that the power system is "plugged" (plugging) The process can also be configured as open circuit control, as shown in Figure 7.

FIG. 7 shows a circuit configuration diagram of a power system 500 in accordance with an embodiment of the present invention. As shown in FIG. 7, the controller 24 receives a current sampling signal I _sense representing the flow through the main power device 21, and generates a switching control signal based on the current sampling signal I _sense to perform overcurrent control. In the embodiment shown in Fig. 7, the duty cycle of the main power device 21 gradually increases from 0% to 100%, and remains 100% after the end of the "plugging" process.

In the ideal case, after the "plugging" process is over, the inductor 23 has no impedance (i.e., a DC short) and does not generate any power dissipation on the inductor 23. In practical applications, the inductor 23 may have parasitic resistance that causes power consumption during normal operation of the power system.

FIG. 8 shows a circuit configuration diagram of a power system 600 in accordance with one embodiment of the present invention. In the embodiment shown in FIG. 8, the power system 600 further includes a first power device 25 coupled in parallel with the buck converter of the hot swap stage 602.

In one embodiment, during the "plug-in" process of the power system, the first power device 25 is controlled to be in an OFF state, and the main power device 21 is controlled to operate in a switch mode to transmit the supply voltage V _IN To the load level; after the power system "plug in" process ends, the main power device 21 is controlled to be in an OFF state, and the first power device 25 is controlled to be in a long-pass state, that is, having 100% duty Ratio of the switch state.

In one embodiment, during the "plug-in" process of the power system, the first power device 25 is controlled to be in an OFF state, and the main power device 21 is controlled to operate in a switch mode to supply the supply voltage V _IN Transmitting to the load stage; when the "plug-in" process of the power system is nearing the end, such as when the duty cycle of the main power device 21 approaches 90%, the first power device 25 is controlled to operate in the low dropout mode; When the "plug-in" process is substantially completed, the main power device 21 is controlled to be in an OFF state, and the first power device 25 is controlled to be in a long-pass state, that is, a switch state having a 100% duty ratio.

In one embodiment, the first power device 25 includes a controllable semiconductor device, such as a metal oxide semiconductor field effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), and a bipolar junction transistor (BJT). )and many more.

The main power device of the power system described in each of the above embodiments is configured as a down pipe mode, but those skilled in the art will appreciate that the main power device of the power system can also be configured in the upper pipe mode. FIG. 9 shows a circuit configuration diagram of a power system 700 in accordance with an embodiment of the present invention.

In the embodiment shown in FIG. 9, the power system 700 includes a front stage 701 that provides a constant supply voltage V _IN at its output terminal, wherein the front stage 701 includes an output terminal coupled to the front stage 701 and a reference ground. The pre-stage capacitor C _IN is coupled to the output terminal of the pre-stage 701 to receive the supply voltage V _IN and generates an output voltage V _O based on the supply voltage. The hot-swap stage 702 includes: The power device 21 has a first terminal, a second terminal, and a control terminal. The first terminal is coupled to the output terminal of the front stage 701 to receive the power supply voltage V _IN . The freewheeling device 22 is coupled to the main power device 21 . Between the second terminal and the reference ground; the inductor 23 has a first terminal and a second terminal, the first terminal of which is coupled to the second terminal of the main power device 21, and the second terminal of which generates an output voltage V _O ; The controller 24 has a first input terminal, a second input terminal and an output terminal, the first input terminal receiving a current sampling signal I _sense representing the flow through the main power device 21, and the second input terminal receiving the representative output voltage V _O Voltage feedback signal V _FB The controller 24 generates a switch control signal at its output terminal based on the current sampling signal I _sense and the voltage feedback signal V _FB for controlling the main power device 21 to operate in a switch mode; the hot plug stage 702 is based on The main power device 21 is turned on and off to generate a required output voltage V _O ; the power system 700 further includes a load stage 703 coupled to the hot plug stage 702 to receive the output voltage V _O . In one embodiment, the voltage level of the output voltage V _O is substantially equal to the voltage level of the supply voltage V _IN .

In one embodiment, the freewheeling device 22 includes a diode. However, in other embodiments, the freewheeling device 22 may further comprise a controllable semiconductor device, such as a metal oxide semiconductor field effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), and a bipolar junction type. Transistor (BJT) and so on.

FIG. 10 shows a circuit configuration diagram of a power system 800 in accordance with one embodiment of the present invention. The circuit structure of the power system 800 shown in FIG. 10 is similar to that of the power system 100 shown in FIG. 2. Unlike the power system 100 shown in FIG. 2, the power supply voltage provided by the previous stage 801 of the power system 800 shown in FIG. V _IN is a negative voltage with respect to the reference ground. Specifically, in the embodiment shown in FIG. 10, the power system 800 includes a front stage 801 that provides a supply voltage V _IN having a negative voltage level at its output terminal, wherein the front stage 801 includes a coupling. a front-end capacitor C _IN connected between the output terminal of the front stage 801 and the reference ground; the hot-swappable stage 802 includes: a main power device 21 having a first terminal, a second terminal, and a control terminal, the first terminal of which is coupled The output terminal of the pre-stage 801 receives the supply voltage V _IN ; the freewheeling device 22 is coupled between the second terminal of the main power device 21 and the reference ground; and the inductor 23 has a first terminal and a second terminal. The first terminal is coupled to the second terminal of the main power device 21; the controller 24 has a first input terminal, a second input terminal, and an output terminal, and the first input terminal receives a current sample representing the flow through the main power device 21. a signal I _sense whose second input terminal receives a voltage feedback signal V _FB representative of the output voltage V _O , the controller 24 generating a switch control signal at its output terminal based on the current sample signal I _sense and the voltage feedback signal V _FB Switch control The signal is sent to a control terminal of the main power device 21 for controlling the main power device 21 to operate in a switch mode; wherein the hot plug stage 802 is at the inductor 23 based on the on and off of the main power device 21 A desired output voltage V _O is generated between the second terminal and the reference ground. The power system 800 also includes a load stage 803 coupled to the hot plug stage 802 to receive the output voltage V _O .

In one embodiment, the freewheeling device 22 includes a diode. However, in other embodiments, the freewheeling device 22 may further comprise a controllable semiconductor device, such as a metal oxide semiconductor field effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), and a bipolar junction type. Transistor (BJT) and so on.

The operation principle of the power system 800 shown in FIG. 10 is similar to that of the power system 100/200/300/400/500/600/700 shown in FIG. 2/3/5/6/7/8/9, for the sake of brevity, It will not be detailed here.

The power system of the above various embodiments reduces power loss during hot plugging compared to the prior art. Unlike the prior art, the power device of the power system of the above various embodiments operates in a switching mode, which is greatly reduced. The power loss during the "plug in" process optimizes the thermal design of the system. Further, the various embodiments described above control the output voltage to increase slowly such that when the voltage level of the output voltage reaches the input voltage level, the time derivative of the output voltage is substantially zero, thereby eliminating oscillation of the hot plug stage.

Figure 11 shows a flow chart 900 of a method for hot plugging a power system in accordance with one embodiment of the present invention. The method includes: Step 901, placing the hot plug stage and the load stage on a main board, wherein the hot plug stage includes a buck converter having a main power device.

In step 902, the motherboard is plugged into the power system.

Step 903, controlling the main power device to operate in a switch mode to generate an output voltage at an output terminal of the hot plug stage, wherein a duty cycle of the main power device gradually increases from 0% during the plug-in process Up to 100%; the duty cycle of the main power device remains at 100% after the plug-in process and during normal operation of the power system.

In one embodiment, the primary power device is controlled to operate in a switching mode in response to a current, output voltage, and voltage reference signal flowing through the primary power device. In one embodiment, the voltage reference signal has a linear growth slope at the beginning, but has an exponential growth slope after a certain point in time.

In one embodiment, the primary power device is controlled to operate in a switching mode in response to a current, current reference signal, output voltage, and voltage reference signal flowing through the primary power device.

In one embodiment, the method further includes controlling the second power device to be turned on after the plug-in process ends to short the hot plug stage.

While the invention has been described with respect to the exemplary embodiments illustrated embodiments The present invention may be embodied in a variety of forms without departing from the spirit or scope of the invention. It is to be understood that the above-described embodiments are not limited to the details of the foregoing. It is to be understood that all changes and modifications that come within the scope of the claims or the equivalents thereof are intended to be covered by the accompanying claims.

10‧‧‧Hot-plug power system

11‧‧‧Pre-level

12‧‧‧Hot-plug stage

13‧‧‧Load level

21‧‧‧Main power unit

22‧‧‧Continuous flow device

23‧‧‧Inductors

24‧‧‧ Controller

100‧‧‧Power system

101‧‧‧Previous

102‧‧‧Hot-plug stage

103‧‧‧Load level

41‧‧‧current comparator

42‧‧‧Amplifier

43‧‧‧Logical drive unit

200‧‧‧Power System

201‧‧‧Previous

202‧‧‧Hot-plug stage

203‧‧‧Load level

44‧‧‧Voltage reference signal generator

45‧‧‧index signal generator

46‧‧‧Linear signal generator

51‧‧‧Voltage source

52‧‧‧Resistors

53‧‧‧First capacitor

54‧‧‧ Output node

61‧‧‧current source

62‧‧‧second capacitor

300‧‧‧Power system

301‧‧‧Pre-level

303‧‧‧Load level

400‧‧‧Power system

401‧‧‧Previous

402‧‧‧Hot-plug stage

403‧‧‧Load level

500‧‧‧Power system

501‧‧‧Previous

502‧‧‧Hot-plug stage

503‧‧‧Load level

600‧‧‧Power System

601‧‧‧Previous

602‧‧‧Hot-plug stage

603‧‧‧Load level

25‧‧‧First electrical installation

700‧‧‧Power system

701‧‧‧Previous

702‧‧‧Hot-plug stage

703‧‧‧Load level

800‧‧‧Power system

801‧‧‧Previous

802‧‧‧hot plug stage

803‧‧‧Load level

Figure 1a shows a schematic diagram of the circuit structure of the existing hot-swappable power system 10; Figure 1b shows the hot-swappable power system 10 of Figure 1a at the output voltage V _O , the MOSFET M1 汲 extreme (D) and the source terminal (S Schematic diagram of the voltage drop V _DS , the current I _S flowing through the MOSFET, and the power consumption P_ _MOS of the MOSFET M1; FIG. 2 is a schematic diagram showing the circuit structure of the power system 100 according to an embodiment of the present invention; A schematic diagram of a circuit configuration of a power system 200 in accordance with an embodiment of the present invention; FIG. 4 is a schematic timing diagram of a voltage reference signal V _ref in the power system 300 of FIG. 3; A schematic diagram of the circuit structure of the power system 300 of one embodiment; FIG. 6 is a schematic diagram showing the circuit structure of the power system 400 according to an embodiment of the present invention; and FIG. 7 shows the circuit structure of the power system 500 according to an embodiment of the present invention. FIG. 8 is a schematic diagram showing the circuit structure of a power system 600 according to an embodiment of the present invention; FIG. 9 is a schematic diagram showing the circuit structure of a power system 700 according to an embodiment of the present invention; The invention is a schematic circuit diagram of the electric power system 800 of the embodiment; FIG. 11 shows a method for hot-swap power system in accordance with one embodiment of the present invention, 900 of flowchart.

21‧‧‧Main power unit

22‧‧‧Continuous flow device

23‧‧‧Inductors

24‧‧‧ Controller

100‧‧‧Power system

101‧‧‧Previous

102‧‧‧Hot-plug stage

103‧‧‧Load level

Claims (10)

A hot-swappable power system includes: a front stage that provides a constant supply voltage at an output terminal thereof, wherein the front stage includes a front stage capacitor coupled between the front stage output terminal and a reference ground; and a hot swap stage, Is coupled to the output terminal of the pre-stage to receive the supply voltage, and generates an output voltage based on the supply voltage, the hot-swap stage comprising: a buck converter having a main power device and a controller, the controller including the first input a terminal, a second input terminal and an output terminal, the first input terminal receiving a current sampling signal representing the flow through the main power device, the second input terminal receiving a voltage feedback signal representing the output voltage, the controller is based on the current sampling signal and the voltage The feedback signal generates a switch control signal at its output terminal for controlling the main power device to operate in a switch mode, the hot plug stage generates an output voltage based on the on/off of the main power device; and the load stage is coupled to The stage is hot plugged to receive the output voltage. The power system of claim 1, wherein the buck converter further comprises: a freewheeling device having a first terminal and a second terminal, the first terminal of which is coupled to the main power device; the inductor a first terminal and a second terminal, the first terminal of which is coupled to the first terminal of the freewheeling device; wherein a potential difference between the second terminal of the freewheeling device and the second terminal of the inductor is the output Voltage. The power system of claim 1, wherein the controller comprises: a current comparator having a first input terminal, a second input terminal, and an output terminal, the first input terminal receiving a current sampling signal representing a flow through the main power device, and the second input terminal receiving a current reference signal, the current comparator being based The current sampling signal and the current reference signal generate a current comparison signal at its output terminal; the voltage reference signal generator provides a voltage reference signal having a linear growth slope at the beginning, but having an index after a certain time point a growth slope; an amplifier having a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal receives the voltage feedback signal, and the second input terminal is coupled to the voltage reference signal generator to receive the voltage reference signal, the amplifier Generating an amplified signal at an output terminal thereof based on the voltage feedback signal and the voltage reference signal; and a logic driving unit having a first input terminal, a second input terminal, and an output terminal, the first input terminal of which is coupled to the output of the current comparator The terminal receives the current comparison signal and the second input thereof Line is coupled to the output terminal of the amplifier to receive the amplified signal, the driving unit based on the logic of the comparison signal and the amplified current signal to generate the switching control signal at its output terminal. The power system of claim 3, wherein the voltage reference signal generator comprises: an index signal generator that generates an exponential signal having an exponentially increasing slope; and a linear signal generator that produces a linear signal having a linear growth slope And a selector having a first input terminal, a second input terminal, and an output terminal, the first input terminal being coupled to the index signal generator for receiving the index signal, and the second input terminal coupled to the linear signal generating The device receives a linear signal, and the selector uses a signal having a lower voltage level as a voltage reference signal of its output terminal based on the index signal and the linear signal. The power system of claim 1, further comprising: a first power device coupled in parallel with the buck converter of the hot plug stage; wherein in the "plugging in" process of the power system, A power device is controlled to be in an off state, the main power device is controlled to operate in a switch mode; and after the power system "plug in" process is finished, the main power device is controlled to be in an off state, and the first power device is controlled to become Long-pass status. A hot-swappable power system includes: a front stage that provides a constant supply voltage at an output terminal thereof, the front stage includes a front stage capacitor coupled to the front stage output terminal and the reference ground; and the hot plug stage is coupled to The output terminal of the pre-stage receives the supply voltage and generates an output voltage based on the supply voltage. The hot-swap stage includes: a main power device having a first terminal, a second terminal, and a control terminal, the first terminal of which is coupled to The output terminal of the front stage receives the power supply voltage; the freewheeling device is coupled between the second terminal of the main power device and the reference ground; the inductor has a first terminal and a second terminal, and the first terminal is coupled a second terminal of the main power device, the second terminal of which generates the output voltage; the controller has a first input terminal, a second input terminal, and an output terminal, An input terminal receives a current sampling signal representing a flow through the main power device, a second input terminal thereof receives a voltage feedback signal representative of the output voltage, and the controller generates a switch control signal at an output terminal thereof based on the current sampling signal and the voltage feedback signal, The main power device is controlled to operate in a switch mode; the hot plug stage generates an output voltage based on the on/off of the main power device; and the load stage is coupled to the hot plug stage to receive the output voltage. The power system of claim 6, wherein the controller comprises: a current comparator having a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal receives a representative flow through the main power device a current sampling signal, the second input terminal of which receives a current reference signal, the current comparator generating a current comparison signal at its output terminal based on the current sampling signal and the current reference signal; an index signal generator generating an index signal having an exponentially increasing slope a linear signal generator that produces a linear signal having a linearly increasing slope; and a selector having a first input terminal, a second input terminal, and an output terminal, the first input terminal of which is coupled to the index signal generator to receive the index signal The second input terminal is coupled to the linear signal generator to receive the linear signal, and the selector uses the signal with the lower voltage level as the voltage reference signal of the output terminal based on the index signal and the linear signal; Having a first input terminal, a second input terminal, and an output terminal, the first input thereof The terminal receives the voltage feedback signal and its second input terminal Is coupled to an output terminal of the selector to receive a voltage reference signal, the amplifier generates an amplified signal at an output terminal thereof based on the voltage feedback signal and the voltage reference signal; and a logic driving unit having a first input terminal, a second input terminal, and An output terminal, the first input terminal is coupled to the output terminal of the current comparator to receive the current comparison signal, and the second input terminal is coupled to the output terminal of the amplifier to receive the amplified signal, and the logic driving unit compares based on the current The signal and the amplified signal are generated at their output terminals. A hot-swappable power system includes: a front stage that supplies a supply voltage having a negative voltage level at an output terminal thereof, the front stage including a front stage capacitor coupled between the front stage output terminal and a reference ground; The first power terminal has a first terminal, a second terminal, and a control terminal, and the first terminal is coupled to the output terminal of the front stage to receive the power supply voltage; and the freewheeling device is coupled to the main power device. Between the second terminal and the reference ground; the inductor has a first terminal and a second terminal, the first terminal of which is coupled to the second terminal of the main power device; the controller has a first input terminal and a second input a terminal and an output terminal, the first input terminal receiving a current sampling signal representing a flow through the main power device, the second input terminal receiving a voltage feedback signal representative of the output voltage, the controller based on the current sampling signal and the voltage feedback signal at the output thereof And generating a switch control signal for controlling the main power device to operate in a switch mode; wherein the hot plug stage is based on the on/off of the main power device Two terminal The output voltage is generated between the reference ground and the reference ground; the load stage is coupled to the hot plug stage to receive the output voltage. The power system of claim 8, wherein the controller comprises: a current comparator having a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal receives a representative flow through the main power device a current sampling signal, the second input terminal of which receives a current reference signal, the current comparator generates a current comparison signal at its output terminal based on the current sampling signal and the current reference signal; the voltage reference signal generator provides a variable voltage reference signal When the voltage level of the output voltage substantially reaches the voltage level of the power supply voltage, the time derivative of the voltage reference signal is zero; the amplifier has a first input terminal, a second input terminal, and an output terminal, and the first input terminal thereof Receiving a voltage feedback signal, the second input terminal is coupled to the voltage reference signal generator to receive the voltage reference signal, the amplifier generates an amplified signal at the output terminal thereof based on the voltage feedback signal and the voltage reference signal; and the logic driving unit has a first input terminal, a second input terminal, and an output terminal, the An input terminal is coupled to the output terminal of the current comparator to receive the current comparison signal, and a second input terminal is coupled to the output terminal of the amplifier to receive the amplified signal, and the logic driving unit is based on the current comparison signal and the amplified signal. The switch control signal is generated at its output terminal. A method for hot plugging a power system, comprising: The hot plug stage and the load stage are placed on a main board, wherein the hot plug stage includes a buck converter having a main power device; the main board is plugged into the power system; and the main power unit is controlled to operate in a switch mode, Generating an output voltage at an output terminal of the hot plug stage, wherein the duty cycle of the main power device is gradually increased from 0% to 100% during the plug-in process; after the plug-in process ends and in the power system During normal operation, the duty cycle of the main power device remains at 100%.